If I understand you, what you mean is something like

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strFormName = 'CLIEN50ED'
strProcName = 'Show'
CallByName strFormName, strProcName, VbMethod
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I've tried it, it doesn't work. The first parameter is of type Object. If strFormName is a String; it give a 'Type Mysmatch', if it's Variant; you get an 'Object Required' when calling the function.